JPS5946100B2 - semiconductor equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a semiconductor device with improved lead wires.

In recent years, diode-type and transistor-type semiconductor devices have been each improved, but the present invention was made with a particular focus on lead wires, and improves the strength, ductility, solderability, and bondability of lead wires with resin. A preferable semiconductor device is provided.

Conventionally, lead wires for semiconductor devices have mainly been made of pure Ni or 50Ni--Fe alloys, which have excellent strength and bendability. However, since this lead wire has poor solderability, recently lead wires mainly made of copper have been used. Lead wires made mainly of copper are preferable because they have good solderability and good conductivity, but when used in semiconductor devices in which semiconductor elements are molded with resin, they have the following difficulties and recommendations: It was hot.

In other words, common copper alloys have high thermal conductivity.

Therefore, when a resin-molded semiconductor device is soldered to a predetermined location, the heat of the solder bath is likely to be transmitted through the lead wires, causing the resin temperature in the molded portion to rise excessively. Therefore, the bonding force of the resin becomes weak, and the expansion and contraction of the lead wire combine to cause the lead wire to become loose, causing the lead wire to wobble and hinder subsequent processes. Therefore, an object of the present invention is to provide an excellent semiconductor device in which the bondability with resin is particularly improved without impairing the strength, bendability, and solderability of lead wires mainly made of copper. be.

In the semiconductor device according to the present invention, the lead wire is made of Ni5 by weight%.
It is characterized in that it is formed of an alloy consisting essentially of Cu in an amount of 20% to 20%, preferably 8 to 15%, and 5 to 30% Fe, preferably 15 to 20% with the remainder being Cu.

To explain the reason for limiting each component, Ni and Fe improve strength, but if they are contained in a large amount, they deteriorate the fernability, and if they are contained in a small amount, the thermal conductivity increases. Range is preferred. Examples of the present invention will be described below. An ingot with the composition shown in Table 1 was melted.
0.4 after hot working at 900-1000℃ and then cold working
A wire rod of 55-φ was annealed at 500 to 700°C and used as a sample. Table 2 shows the stiffness, D bendability, and electrical conductivity of these samples. In addition, after embedding the sample in resin, soldering was performed to examine solderability and the state of bonding with the resin. The results are shown in Table 3. Repetitive bendability is expressed as the number of times until breakage occurs after 9" bending is repeated under a load of 450g at 0.5R, and solderability and bondability with resin are each expressed as the number of defects in 100 samples.

Here, to determine the quality of solderability, the obtained lead wire sample was immersed in 40Pb-Sn solder at about 230° C. for about 5 seconds, and those with peeling of the solder were judged as defective.

In addition, to check the bondability with the resin, embed one end of the lead wire sample in the epoxy resin for about 5 mm, solder the other end under the above conditions, bend the lead wire sample at an angle of about 90 degrees, and then turn it horizontally about 90 degrees. Therefore, samples where the lead wire sample separated from the resin and rotated were considered defective. As is clear from Table 3, the lead wire, which is a feature of the device of the present invention, has no defects in terms of solderability and bondability with resin, and is significantly different from conventional lead wires in this respect. It is something. Furthermore, according to Table 2, the lead wire according to the present invention has favorable strength as indicated by stiffness and ductility as indicated by the number of repeated bending, and conductivity is also sufficient for practical use as it is equivalent to that of 50Ni-Fe alloy. . When a transistor-type semiconductor device formed using such lead wires was actually used for various purposes, it was found to be extremely robust and excellent even when attached by soldering. Furthermore, since the lead wire according to the device of the present invention is a magnetic material, it is preferable because it has good workability in the soldering process.

As described above, the semiconductor device of the present invention is an excellent device formed using improved lead wires, and has high industrial value.

Claims (1)

[Scope of Claims] A semiconductor device characterized in that a lead portion is formed of an alloy consisting of 5 to 20% Ni, 5 to 30% Fe, and the remainder substantially Cu at 1% by weight. 2. The semiconductor device according to claim 1, wherein Ni is 8 to 15%. The semiconductor device according to claim 1, wherein 3 Fe is 15 to 20%.